This Non-provisional application claims priority under 35 U.S.C. xc2xa7119(a) on Patent Application No(s). 092218610 filed in Taiwan on Oct. 20, 20003, the entire contents of which are hereby incorporated by reference.
The present invention relates to a gear rack adjustment wheel for circular knitting machines to adjust an adjustable sliding block to a correct position for a smooth and precise knitting operation.
Referring to FIG. 1, a conventional cam fine-tuning apparatus includes a straddle dock 11, a sliding block 12 coupled on the straddle dock 11 that has a plurality of cams 16 fastened thereon, a fine-tuning assembly 13 located on the straddle dock 11 that has a screw thread, a retaining member 14 located respectively on an upper edge and a lower edge of the straddle dock 11, and a spring 15 located between the retaining member 14 at the lower edge of the straddle dock 11 and the sliding block 12.
The fine-tuning assembly 13 has a first sloped surface 131 extending into a trough 121 of the sliding block 12 to be in contact with a second sloped surface 1211 formed on the trough 121. When the fine-tuning assembly 13 is turned, it is moved outwards from the straddle dock 11 along the screw thread. The fine-tuning assembly 13 presses the sliding block 12, with the first sloped surface 131 ramming the second sloped surface 1211 so that the sliding block 12 is pushed downwards along the first sliding surface 131. By contrast, when the fine-tuning assembly 13 is turned in the reverse direction, it is moved into the straddle dock 11 along the screw thread, and the spring 15 located between the retaining member 14 at the lower edge of the straddle dock 11 and the sliding block 12 will push the sliding block 12 upwards along the first sloped surface 131.
The spring 15, located between the retaining member 14 at the lower edge of the straddle dock 11 and the sliding block 12 is in a compressed state. After repeated use elastic fatigue or fatigue failure occurs, i.e. the elasticity weakens or disappears altogether. As a result, the sliding block 12 cannot return to its original position. Therefore, the circular knitting machine cannot operate properly and fails to knit correctly. Moreover, the service life of the spring 15 is limited and often requires replacement. Repairing a knitting machine is both costly and time consuming. Replacing parts not only increases overheads, while the machine is out of commission throughput is decreased.
Therefore the present invention aims at providing an improved fine-tuning mechanism that can precisely adjust the sliding block to the correct position, thus enabling the circular knitting machine to achieve a smooth and precise knitting operation.
The primary object of the invention is to solve the aforesaid disadvantages. The invention includes an adjustable sliding block which has a gear rack and an adjustment wheel containing a screw thread. The screw thread couples to the gear rack so that the adjustable sliding block can slide along the track of the adjustment wheel. Thereby the sliding block can be adjusted to the correct position to achieve a smooth and precise knitting operation.
The gear rack adjustment wheel according to the invention includes a holding deck located on a circular knitting machine, an adjustable sliding block slides along the bottom of the holding deck which has a gear rack formed on a lateral side, a sliding trough in the holding deck to communicate with the adjustable sliding block, an aperture formed on one side of the holding deck, and an adjustment mechanism which includes an adjustment wheel and an anchor pin for the adjustment wheel. The adjustment wheel is housed in the sliding trough which communicates with the adjustable sliding block so that the adjustment wheel can be in contact with the adjustable sliding block and adjust the adjustable sliding block. The adjustment wheel has a screw thread which may be coupled with the gear rack of the adjustable sliding block, a nut which has a scale to indicate the adjustment degree, and an annular ring spaced from the nut to form a gap to be wedged by the anchor pin to anchor the adjustment wheel at a desired position. The anchor pin is housed in the aperture in the holding deck.
Through the movement of the adjustment wheel, the relative position of the gear rack of the adjustable sliding block and screw track of the adjustment wheel may be altered, and the position of the adjustable sliding block may be adjusted.
The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.